anyway, typically if you are baking sculpty that's already on plastic, you don't want the head higher than 175 degrees. cook it longer, contantly checking the condition of the plastic (make sure it's not too hot to touch...soon after that it will melt.

about 30-45 minutes and a small peice like you are showing should be dry.

To be on the safe side, I find it's often best to bake in shorter bursts, the same way I do layered sculpting.
Stick it in for 20 minutes or so at about 275 degrees Fahrenheit (130 Celsius, or Gas Mark 1/2 in my oven); once it's cooled down you can do any necessary adding and reworking and give it another 20. For the final bake I'll put it in for 30 minutes.